RTO on a field limited takeoff-where do I end up?
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framer,
Everything that you say is true
No further comment is necessary, excepting that you've brought up one more 'it depends' to add to the list. Recognition, reaction, and putting Stopping action into effect times are just one more thing that has changed over the years. (It's also the reason that I cautiously say Recognition and Reaction times in posts rather than quoting the number of seconds, it varys).
Without second guessing Mutt, this is again one more reason for his asking from which era the aircraft was certified.
Regards,
Old Smokey
Everything that you say is true
No further comment is necessary, excepting that you've brought up one more 'it depends' to add to the list. Recognition, reaction, and putting Stopping action into effect times are just one more thing that has changed over the years. (It's also the reason that I cautiously say Recognition and Reaction times in posts rather than quoting the number of seconds, it varys).
Without second guessing Mutt, this is again one more reason for his asking from which era the aircraft was certified.
Regards,
Old Smokey
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The original question asked where an aircraft would end up following an RTO at V1 at a Runway Limited Weight on a wet runway. I would say that for older pre 1981 aircraft such as the B707,B727,B737-100/200, B747-100/200/300/SP, DC-8, DC-9, DC-10, MD-80, certified under FAR25, they are guaranteed to end up completely off the end of the runway in the dirt, even on a dry runway. There are a number of reasons for this:
Post 1981, things started to change with the use of flight test timings for transition of brakes/throttles/speed brakes followed by a 2 second buffer at Vb speed. There was also a great improvement in the available software such as accounting for line-up distances. This would have applied to the B757,B767, B747-400, B737-300/400/500.
In 1995 with the certification of the B777-200/300, MD11 and MD90, they started to apply “Amendment 42”, this allowed 2 seconds at continued acceleration followed by timings for flight test transition of brakes/throttles/speed brakes. The use of worn brakes was introduced as well as the first digital aircraft flight manual chapter 4 for the B777. This method required the longest stopping distance. Boeing also started to introduce operations manual data based on FAA AC91-6A/B, this accounted for specific Mu factors associated with different runway contaminants.
In 1998, the certification of the B737-NG, B757-300, B767-400 and B717 introduced Amendment 92, this allowed for 2 seconds constant speed at V1, followed by timings for flight test transition of brakes/throttle/ speed brakes. This was also the first time that WET runway data was incorporated into an FAA AFM.
That’s the FAA history, I presume that there is an equivalent for UK CAA or DGAC regulations.
We conducted tests in a Level D Full Flight B747-300 simulator using the appropriate software to train crews to get used to high speed RTO’s, we were never able to get the simulator stopped on the runway even with the use of thrust reversers, we queried the simulator manufacturer and Boeing about this, the answer from both was that it “should” stop on the runway as per certification. We conducted the same test with B772 and B744 FFS with carbon brakes, they stopped easily within the runway length.
So you see that there is no easy specific answer, it all depends on where your aircraft was certified, and when!
Mutt
Post 1981, things started to change with the use of flight test timings for transition of brakes/throttles/speed brakes followed by a 2 second buffer at Vb speed. There was also a great improvement in the available software such as accounting for line-up distances. This would have applied to the B757,B767, B747-400, B737-300/400/500.
In 1995 with the certification of the B777-200/300, MD11 and MD90, they started to apply “Amendment 42”, this allowed 2 seconds at continued acceleration followed by timings for flight test transition of brakes/throttles/speed brakes. The use of worn brakes was introduced as well as the first digital aircraft flight manual chapter 4 for the B777. This method required the longest stopping distance. Boeing also started to introduce operations manual data based on FAA AC91-6A/B, this accounted for specific Mu factors associated with different runway contaminants.
In 1998, the certification of the B737-NG, B757-300, B767-400 and B717 introduced Amendment 92, this allowed for 2 seconds constant speed at V1, followed by timings for flight test transition of brakes/throttle/ speed brakes. This was also the first time that WET runway data was incorporated into an FAA AFM.
That’s the FAA history, I presume that there is an equivalent for UK CAA or DGAC regulations.
We conducted tests in a Level D Full Flight B747-300 simulator using the appropriate software to train crews to get used to high speed RTO’s, we were never able to get the simulator stopped on the runway even with the use of thrust reversers, we queried the simulator manufacturer and Boeing about this, the answer from both was that it “should” stop on the runway as per certification. We conducted the same test with B772 and B744 FFS with carbon brakes, they stopped easily within the runway length.
So you see that there is no easy specific answer, it all depends on where your aircraft was certified, and when!
Mutt
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The B737 will stop at the ASDA plus the line-up allowance (because FAR 25 does not require consideration of line-up allowance, whereas the JAR does).
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Absolutely true hvogt, within the 'operating state' (Europe in this case) the local requirements apply for operations, i.e. the B737 must consider line-up allowance if operated under EU-OPS.
In the B737's 'Native State' (USA), the local rules apply, and an RTO would end up off the end of the runway under limiting conditions.
Just one more 'It Depends'..............
Best Regards,
Old Smokey
In the B737's 'Native State' (USA), the local rules apply, and an RTO would end up off the end of the runway under limiting conditions.
Just one more 'It Depends'..............
Best Regards,
Old Smokey
